I don't know what project you plan on painting, but if you do go the metal paint route, I highly recommend getting a gravity fed sprayer from Harbor Freight. They are often on sale for $10 and will make the job so unbelievably simple. The trick with the patina is to spray it on while the paint is evenly wet. Good luck!
Going to be making a pair of fogging grim reaper pillars connected by a faux cast iron arch with foam lit jack o lanterns resting all along the top. For the local halloween fsstival. Im just not great with paint lol
I just finished a few drawer pulls, these were brass, I added some teal acrylic craft paint, black craft paint (wiped it off) and then added small amounts of amber shellac, spritzed with water to achieve the white, flaky corrosion.